Other Significant Transactions (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Schedule of Financial Position Related to Legally Sold Portfolio [Line Items]
Real estate, net	$ 5,224,875	$ 5,391,209
Cash and cash equivalents	29,186	55,751	67,622	84,413
Other assets	470,328	505,416
Total assets	5,937,463	6,079,413
Total indebtedness	3,962,236	4,388,185
Accrued and other liabilities	288,688	287,595
Total liabilities	4,414,999	4,826,716
Noncontrolling interests in consolidated real estate partnerships	234,076	233,008
Equity attributable to Aimco and the Aimco Operating Partnership	(18,772)	(27,721)
Total liabilities and equity	5,937,463	6,079,413
Napico Portfolio [Member]
Schedule of Financial Position Related to Legally Sold Portfolio [Line Items]
Noncontrolling interests in consolidated real estate partnerships	45,267	35,818
Equity attributable to Aimco and the Aimco Operating Partnership	1,616	2,736
Total liabilities and equity	159,660	163,849
Napico Portfolio [Member] | Other Assets [Member]
Schedule of Financial Position Related to Legally Sold Portfolio [Line Items]
Real estate, net	119,416	120,175
Cash and cash equivalents	21,448	22,602
Investment in unconsolidated real estate partnerships	8,065	10,817
Other assets	10,731	10,255
Total assets	159,660	163,849
Napico Portfolio [Member] | Accrued liabilities and other [Member]
Schedule of Financial Position Related to Legally Sold Portfolio [Line Items]
Total indebtedness	106,642	106,032
Accrued and other liabilities	6,135	19,263
Total liabilities	$ 112,777	$ 125,295